BLOOD BRAIN BARRIER ABSTRACT The proposed meeting to be held at Cold Spring Harbor Laboratory (CSHL) on the ?Blood-Brain Barrier? (BBB) on December 7th-10th 2016, will assemble leaders in the BBB field to discuss recent discoveries and future directions. This proposal seeks support for the fourth of a biennial series of meetings held at CSHL on the BBB. This meeting has emerged as a premiere scientific conference in the BBB field. In contrast to other meetings focused on the BBB, the CSHL BBB meeting focuses on the molecular and cellular mechanisms of BBB biology as it relates to development, function, and disease. It is emphasizes molecular genetic and model organism approaches to dissecting BBB biology. Topics to be discussed for the 2016 meeting will include: i. BBB Development; ii. The Functional BBB; iii. Emerging BBB Model Systems; iv. Molecular BBB Transport; v. The aging and diseased BBB; vi. Functional interactions at the neuro-vascular unit. Given the recent fundamental discoveries in the BBB field, and the diverse approaches and models currently employed to unravel BBB biology, communication among international researchers is essential to continue to advance research focused on the BBB. Two leading scientists will chair each session and selected speakers primarily include graduate students, postdoctoral fellows and junior faculty. Two special lectures will be presented to provide essential background critical to stimulating discussion between scientists working on related but distinct areas. There will also be two poster sessions where a majority of participants can present their work. Three posters will be selected for a prize of which the first and second will be presented as late breaking talks. The meeting will be of moderate size, as it has grown steadily from its inception in 2008. We expect >120 participants, including a significant number of students and postdoctoral fellows.